In a Schottky barrier diode (SBD), at an interface between a Schottky electrode made of metal and a semiconductor region, work function difference between the metal and semiconductor is typically small. Because of the material property difference, a leakage current of the SBD may be relatively larger than that of a P-N diode when the diodes are reverse-biased.
To suppress the leakage current of an SBD, Japanese Patent Application Publication No. 2000-294804 shows a configuration, in which a P-N diode is disposed on a part of Schottky junction. More specifically, multiple P type layers having a stripe and projected structure are disposed around a contact region between a Schottky electrode and a surface part or an inside of a drift layer.
In the configuration shown in Japanese Patent Application Publication No. 2000-294804, however, since the P type layers have the stripe structure, it is considerably difficult to design an overlap part where the P type layers overlaps with a termination structure. The terminal structure includes a resurf layer and a guard ring layer, and surrounds a cell in which SBD formed. It has been therefore difficult to provide an SiC semiconductor device having an SBD, the SiC semiconductor device being capable of reducing the leakage current when the SBD is reverse-biased and having a high breakdown voltage and high yield ratio.